1. Field of the Invention
The present invention is directed to a remotely controllable circuit breaker incorporating an electromagnet which responds to a remote control signal for closing and opening a breaker contact, and more particularly to such a remotely controllable circuit breaker with an improved space saving structure.
2. Description of the Prior Art
Remotely controllable circuit breakers using an electromagnet for closing and opening the breaker contact are well known in the art, for example, as disclosed in U.S. Pat. Nos. 4,598,263, 4,682,132, and 4,700,160. The prior art breakers include a pair of first and second movable contact arms carrying first and second contacts, respectively. The first contact arm is operatively connected to a manual switching mechanism for manual contact closing and opening, while the second contact arm is operatively connected to an electromagnet for contact closing and opening in response to a remote control signal. The second contact arm is in the form of L-shaped actuator with vertical and horizontal members and carries the second contact on its one member and has the other member connected to a movable part of the electromagnet. The L-shaped second contact arm is pivotally supported at the connection between the angled members for pivotal movement about a pivot axis as it is driven by the electromagnet. In the prior breakers, the L-shaped second contact arm is not intended to be disposed in a closely adjacent relation to the electromagnet and requires a relatively large mounting space in the vicinity of the electromagnet. That is, either or both of the vertical and horizontal members of the L-shaped second contact arm extend in a direction away from the electromagnet. Because of such space consuming structure, the prior breaker is difficult to be made compact enough to be installed as a replacement breaker of remote control capability for an existing breaker without such capability. Further, the space consuming structure is found particularly disadvantageous when the electromagnet of greater dimensions and therefore having an increased driving force is required within a limited space for reliable electromagnet actuation in response to a remote control signal.